Controlling end play of rotary machines.



N0. 66|,049- Patented Nov. 6, |900.

, E. M. HEWLETT.

CONTROLLING END PLAY 0F ROTARY MACHINES.

(Application led'Aug. 81, 1900.)

(No Model.)

inventor? Edw ardM.Hevvlett UNITED STATES PATENT OFFICE.

EDWARD M. HEWLETT, OF SCIIENECTADY, NEW YORK, ASSIGNOR TO TI'IE GENERAL ELECTRIC COMPANY, OF NEW YORK.

CONTROLLING EN D PLAY OF ROTARY MACHIN ES.

SPECIFICATION forming part of Letters Patent No. 661.049, dated November e, 1900.

Application filed August 3l. 1900. serial No. 28,651. (No model.)

T all whom it may concern: field-magnets, the weight of the parts, and

Beit known that I, EDWARD M. HEWLETT, a the inclination of the machine. citizen oftheUnited States, residingat Schen- In carrying out the invention I employ a ectady, county of Schenectady, State of New common exciting-circuit for the several end- 55 5 York, have invented certain new and useful play magnets, the closure of which is effected Improvementsin ControllingEnd Playof Roby a timing device which holds the circuit tary Machines, (Case No. 1,050,) of which the closed for a suiicient interval to permit the following is a specification. shaft to be drawn up to the magnet and then In operating many types of machines where opens it, and after a further determined in- 6o lo one of the parts is mounted on a revolving` terval closes it again.

shaft it is desirable to control the end play of My invention involves an end-play device the shaft and to render it periodic. In such the controlling force of which is adjusted types of machines as dynamo-electric marelatively to the period of the movable part, chnes, electric motors, or rotary converters also a common controlling-circuit for a plu- 65 I5 it is especially desirable to have the shaft rality of end-play devices, and means for closperiodic in its lateral motion relatively to the ing and opening of the circuit for a deterbrushes, since where there is no end play a minate period to establish the desired rate of grooving of the commutator results, which lateral oscillation of the shaft. interferes with the proper engagement of the It comprises also other features of novelty 7o "i zo brushes and causes sparking and pitting of in the controlling-circuits and features of the commutator-bars. In machines which construction in the controlling mechanism, are beltdriven the shaft is kept in to-andwhich will be hereinafter more fully defro lateral movement by reason of the play of scribed and will be definitely indicated in the belt over the pulleys; but in direct-conthe claims. 75 nected machines and in rotary converters the In the accompanying drawings, illustratshaft is held in a fixed position with relation ing the invention, Figure l is a longitudinal to its bearings by the field-magnets, and unsectional elevation of a controlling device less provisions are made to positively secure for end play. Fig. 2 is a top plan view of the end play the commutator is Worn into a same, and Fig. 3 is a diagram of the control- 8o 3o groove. Devices have accordingly been proling-circuits.

vided for securing a to-andfro lateral move- Referring first to the diagram, l represents ment of the shafts of such machines. Some a shaft opposite the end of whichis'mppnted of these involve the employment of an elecan end-play magnet 2, which when energized tromagnet mounted on a bracket or frame to draws up the shaft. In an electromagnetic 8f face the end of the rotary shaft, which is device, such asa rotary converterordynamoperiodically energized by an electric current electric machine or motor, the shaft is drawn and imparts a lateral thrust of the shaft, up, so as to shift it laterally againstits magthereby effecting a lateral movement in its netic field of force, which when the magnet bearings, and thus causing the commutator is denergized draws it back again. Ina ma- 9o 4o to Wear more uniformly over its entire or a chine of other character a control -spring large portion of its face; but so far as I know might be used to effect the return of the shaft. none of these devices were organized so that The same controlling-circuit mayinclude any a proper adjustment of the controlling` force desired number of end-play magnets forother could be made to suit the natural period of machines, as indicated at 2n 2b 2c. The con- 95' oscillation of the shaft. My invention introlling-circuit includes a circuit-closer 3, volves apparatus for effecting this result on mounted on the end of a rod secu red to an iron any desired number of machines by a single core 4 et, controlled by a solenoid 5 5, formed controlling device, means being provided by of two sections, which may be differentially which the periods of end play may be adconnected, as will be hereinafter more fully roo 5o justed. The period of the shaft is not always described. Cooperating with the contact 3, the same, as it varies with the strength of the which is formed of a number of thin strips of 'engages the contact 9.

phosphor-bronze or other good conducting metal, mounted so that its ends can effect an elastic engagement, isa pair of fixed contacts 6 6, The contacts 6 6 are mounted in cooperative relation to a magnetic field established by a coil 7, which acts as a blow-out to extinguish the arc when the circuit is opened. When the core 4 is lifted, it effects a slow movement of a pivoted contact-lever S, playing between two fixed stops 9 10. The movement of the lever S is retarded by a timing device, so that a regular interval of time elapses after leaving its contact 10 before it Assuming that the wires plus and minus represent the two leads of a charging-circuit, the minus-wire may be connected with one terminal of the coil 5, the other terminal being connected with one end of the coil of the end-play magnet., the other end of the magnet-coil being` connected with the positive wire. Vhere currents of considerable potential are employed, a resistance 11 may be included in the circuit. A similar arrangement of the end-play coils of other machines that may be controlled by the same circuit is made, as indicated at 11 11b 11C. In shunt to the branch, including the lever 8 and the coil 5, is a branch including the contacts G 6 and the blow-out coil 7. The coils 5 5 form a continuous winding, the middle point of which is connected in circuit with the end-play magnet, as already described, and the upper point of which is connected with the positive main by a wire 12. It will thus be seen that when the lever S engages the contact 10 a circuit is closed by way of wire 13, lever S, and wire 14 to the negative main and by wayof both coils 5 and 5 and wire 12 to the positive main, plunger 4 is lifted, and the contacts 6 6L bridged by elastic contact 3. The circuit is then made through the end-play magnets by way of wire 15, resistance 11, contacts 6 6, and blow-out coil 7 to the negative main. The shaft 1 is thereby drawn to the magnet. Simultaneously the upward movement of the core through the instrumentality of the time device is gradually carrying the contact-lever 8 away from contact 10 and after a determinate interval brings it into engagement with contact 9. rlhis establishes a new circuit from the positive main by way of contact 9, lever S, wire 13, coil 5, contacts 6 6, and coil 7 back to the negative niain,which by its differential action demagnetizes the core 4 and permits it to be thrown by a spring to the position shown in the diagram. During the transit of the lever 8 from contact 10 to contact 9 suliicient energy goes through coil '5 by way of wires 12 16, contacts 6 6, and coil 7 to hold the plunger in its forward position until the differential circuit is established by engagement of the lever S with contact 9, and during this time the end-play magnet is active in moving the shaft, which requires more than a momentary impulse to shift it.

The mechanical organization by which the movements of the controlling` apparatus are governed will be understood from an examination of Figs. 1 and 2, in which the same reference-n umbers indicate like parts to those referred to in the diagram. The parts are supported in a cast-iron frame 17. The plunger is retracted by a helical spring 1S, the tension of which may be governed by an adjusting-screw 19, mounted on a projecting end of the brass tube in which the core nieves and engaging a pin 20, movable along the slot of the tube, as indicated in Fig. 2. Thus the initial tension of the spring` 18 maybe varied, one end of the spring being :fastened to the lever 8 and the other end to a rod 21, connected to the plunger. The rod S carries a gear-sector 22, engaging a time-train, as indicated in dotted lines in Fig. 1, the last shaft of which carries an adjustable ily 22,(see Fig. 2,) the two slotted Yanes of which may be set so as to vary the speed of the train. Vith the lever 8 is connected a spring 23 tothrow the lever to the right when the magnet is deenergized. Blow-out coil 7 has one extended pole formed by the iron casing and the other formed by a plate of iron 24, a box of indurated ber open at the ends being mounted between the two poles, in which box are housed the contacts 6 6 and the movable bridge The parts as thus organized and connected, as indicated in the diagram in Fig. 3, close the circuit through both sections of the solenoid 5 5, drawing in the core 4, compressing the spring 18, and pushing against lever 8. The current is su'llicientlystrong to compress the spring and shift the plunger sufliciently forward to bridge contacts 6 o r1`he time-train permits the lever S to be shifted slowly, during which time the solenoid-circuit is held completed as to one section, as hereinbefore described, and during which the shaft is being drawn laterally. Vhen the lever S engages contact 9, the position indicated in Fig. 1, a new circuit is made, as hereinbefore described, putting the coils 5 5 in opposition, thereby releasing the core 4, and the spring 23 is permitted to slowly return the lever 8 to its normal position, during which time the shaft is drawn away from the end-play magnet. Thus the end-play magnets 2 2 2b 2C of the several machines controlled are periodically energized and deenergized at intervals which may be determined by the adjustment of the fly 22 and the tension of the springs to suit the natural period of oscillation of the shaft, thus producing uniform wear on the commutator. 1f desired to still more accurately adjust the conditions for different machines, the resistances 11 11', the., may be adjusted in each case to a point where the rate of the circuit-closer and the natural rate of the shaft exactly coincide.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent of the United States, is-

IOO

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1. Means for producing end play of a rubbing-surface with relation to a shaft com prising means for periodically shifting one of the engaging parts at intervals corresponding to its period of natural oscillation.

2. Means for producing end play of a rubbing-surface with relation to a shaft comprising means for laterally shifting one of the engaging parts and means for adjusting the periods of shifting action to maintain the said part in oscillation, thereby effecting uuiform Wear.

3. Means for producing end play of a rubbing-surface With relation to a shaft comprising means for laterally shifting one of the engaging parts and adjusting devices for timing the shifting action according to the lateral movement of the shaft.

4. Means for producing end play of a rubbing-surface with relation to a shaft comprising means for shifting one of the engaging parts endwise of the shaft, a controlling electric circuit and an adjustable timing device for determining a periodical charging of the circuit with current.

5. Means for producing end play of a rubbing-surface with relation to a shaft comprising an electromagnet for relatively shifting one of the engaging parts, a circuit including the magnet, a circuit-controller, and a timetrain governing the period of the circuit-controller.

6. Means for producing end play of'a rubbing-surface with relation to a shaft comprising means for laterally shifting one of the engaging parts, and a regulable time-limit-controlling device adapted to effect engagement and disengagement of the shifting device for determinate intervals.

7. Means for producing end play of the shafts of a plurality of machines comprising an end-play magnet on each machine, acommon charging-circuit for the magnets of all machines, and a time-limit circuit-controller for the circuit.

8. Means forproducing end play of a rubbing-surface with relation to a shaft comprising an end-play magnet, a circuit including the same, a circuit-controller, means for periodically operating the circuitcontroller with uniform relation to the lateral excursions of the shaft, and means for retaining the circuit closed to prolong the thrust of the end-play magnet.

9. A time-limit device for electric circuits comprisingamagnetically-operated main circuit-controller in a charging-circuit, an auxiliary circuit-closer controlling the same, a time-limit device for opening the auxiliary circuit-closer, and a demagnetizing-circuit, closed by the auxiliary circuit-closer after a determinate interval of time, to open the main circuit-controller.

l0. A time-limit device for electric circuits comprising a differential magnet, an armature controlled thereby to govern the circuit, a circuit-closer governing the magnet, a timing device lfor the circuit-closer adapted to hold the magnet charged for a determinate interval, and a demagnetizing-contact for neutralizing the magnet at the expiration of said interval.

In witness whereof I have hereunto set my hand this 29th day of August, 1900.

EDWARD M. HEVLETT.

Witnesses:

BENJAMIN B. HULL, CAROLYN L. I-IAYNES. 

